Using the variables self-efficacy, self-estimates, and self-competencies in a hierarchical multiple regression and confirmatory factor analysis, the present study provided strong support for 3 of 6 RIASEC (Realistic, Investigative, Artistic, Social, Enterprising, and Conventional) interest domains regarding Holland's (1997) assertion that it is unnecessary to administer a separate measure of self-efficacy when using the Self-Directed Search (SDS; Holland, Powell, & Fritzsche, 1994) to measure interests in career counseling. Implications for the interpretation of SDS scores in light of self-efficacy assessment are discussed.